LR Max
Local Oaf
I've got a Roamer drive and they recommend the MTL. I'd like to standardize on my transmission/transfer case oil.
Fancy Synthetic oil for transmission, worth it?
- Thread starter LR Max
- Start date
I've got a Roamer drive and they recommend the MTL. I'd like to standardize on my transmission/transfer case oil.
meatblanket
Adventurer
Don't do it. MTL is the consistency of ATF, and it is used in gearboxes that have a pump.
Whine noises at usually not fixable without teardown.
MTL will shift the best. MT90 will be slightly thicker and be slightly more quiet.
Neither one will make problems in your trans that aren't already there.
On all of our manual trans except Porsche type transaxle we use MT90.
MTL will shift the best. MT90 will be slightly thicker and be slightly more quiet.
Neither one will make problems in your trans that aren't already there.
On all of our manual trans except Porsche type transaxle we use MT90.
LR Max
Local Oaf
Do you have a Roamer Drive? Are you using the MT stuff with it? Everything ok?
Just FYI, I thoroughly enjoy all of these inputs. But please elaborate.
meatblanket
Adventurer
No I don't have a Roamer Drive. They share lubricant with the transfer box, right?
My comment is just based on the viscosity that is required/recommended for a Series gearbox/transfer case. MTL is no heavier than 30 wt motor oil. You don't want that in a Series transmission or transfer case. Redline makes higher viscosity GL4 gear oil, such as the MT90 mentioned above. I think if you use the thin stuff it will get even louder, assuming it doesn't cause any damage.
I did have a Fairey once that I filled with Redline "shock proof" synthetic gear oil and it did quiet it down some, so your plan might well work.
My comment is just based on the viscosity that is required/recommended for a Series gearbox/transfer case. MTL is no heavier than 30 wt motor oil. You don't want that in a Series transmission or transfer case. Redline makes higher viscosity GL4 gear oil, such as the MT90 mentioned above. I think if you use the thin stuff it will get even louder, assuming it doesn't cause any damage.
I did have a Fairey once that I filled with Redline "shock proof" synthetic gear oil and it did quiet it down some, so your plan might well work.
tacr2man
Adventurer
I have used Redline in my 110 main gearbox (MTL as its an Lt85 with built in pump) In the transfer box I use their shokpruf heavy . i also use in the diffs . The plus point for diffs over dino oil is if water gets in you can leave it and it will seperate so you can drain it off . I started using in Australia due to 40c+ ambients . It became very popular there with a lot of japanese gearboxes to help protect their 5th gear ! Thats going on about 20years of use so far :smiley_drive:
usual disclaimers no connection etc .
usual disclaimers no connection etc .
Outback
Explorer
Of all of the Synthetics out there AmsOil is one of the top brands. Amsoil was also the first company to offer Synthetic Oils for the Automotive market. The founder was a Jet pilot and wanted the same protection for his personal car that the Synthetics oils gave to his aircraft. A high quality Synthetic oil will offer much more protection for your engine, trans, transcase and gears. Having said that, installing Synthetic oil in a high mileage anything will cause leaks. The seals need to be in good shape. Old dried up seals may still not leak with standard oil but throw in even a cheap low quality synthetic oil and those old seals/gaskets will start to leak. When Amsoil first came out car oil was sold in card board cans (card board sides with metal bottom and top). You simply pushed your metal spout through the metal top and poured. When Amsoil tried to use the card board style cans the synthetic oil just passed through the card board. They ended up going to all metal cans.
On another note. You will see on average a 10% increase in mileage if you use a high quality synthetic oil in the axles, transmission and engine. Also with Amsoil you no longer get a "Dry" start up of your engine in the morning. Amsoil coats the entire inside of your engine which prevents that dry start up. I believe most High Quality Synthetic oil does this as well. Also wear is greatly reduced when you use a high quality synthetic oil so your engines life will be greatly increased as well as any other component that is using synthetic oil. Just remember not all Sythetic Oils are created equal. Not all Petrolium Oils are created equal as well.
On another note. You will see on average a 10% increase in mileage if you use a high quality synthetic oil in the axles, transmission and engine. Also with Amsoil you no longer get a "Dry" start up of your engine in the morning. Amsoil coats the entire inside of your engine which prevents that dry start up. I believe most High Quality Synthetic oil does this as well. Also wear is greatly reduced when you use a high quality synthetic oil so your engines life will be greatly increased as well as any other component that is using synthetic oil. Just remember not all Sythetic Oils are created equal. Not all Petrolium Oils are created equal as well.
DaveInDenver
Middle Income Semi-Redneck
Just to be clear, when this happens it's usually blamed as a downside of synthetic but the reality is that meant your seals are marginal. IOW, if the fluid is cleansing and the crud was all that was sealing things, then you needed to replace them anyway.
I have used Redline MT90 in my W56 and R151F transmissions and standard issue 75W90 in axles and t-cases. There is a noticeable reduction in heat and noise compared to stuff like Castrol Hypoy-C, which isn't a bad fluid by any stretch. But that said, I usually run the Castrol in the axles because it's good enough and changing it more often from water intrusion in particular is more important. I feel if you're spending $40 for diff lube changes you might hesitate and leave bad lube in too long.
The MT90 is nice because it's a GL4 fluid, which means it's A-OK for yellow metals, such as the synchros in Japanese manual transmissions.
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